High Pressure Homogenization of Porcine Pepsin Protease: Effects on Enzyme Activity, Stability, Milk Coagulation Profile and Gel Development
نویسندگان
چکیده
This study investigated the effect of high pressure homogenization (HPH) (up to 190 MPa) on porcine pepsin (proteolytic and milk-clotting activities), and the consequences of using the processed enzyme in milk coagulation and gel formation (rheological profile, proteolysis, syneresis, and microstructure). Although the proteolytic activity (PA) was not altered immediately after the HPH process, it reduced during enzyme storage, with a 5% decrease after 60 days of storage for samples obtained with the enzyme processed at 50, 100 and 150 MPa. HPH increased the milk-clotting activity (MCA) of the enzyme processed at 150 MPa, being 15% higher than the MCA of non-processed samples after 60 days of storage. The enzyme processed at 150 MPa produced faster aggregation and a more consistent milk gel (G' value 92% higher after 90 minutes) when compared with the non-processed enzyme. In addition, the gels produced with the enzyme processed at 150 MPa showed greater syneresis after 40 minutes of coagulation (forming a more compact protein network) and lower porosity (evidenced by confocal microscopy). These effects on the milk gel can be associated with the increment in MCA and reduction in PA caused by the effects of HPH on pepsin during storage. According to the results, HPH stands out as a process capable of changing the proteolytic characteristics of porcine pepsin, with improvements on the milk coagulation step and gel characteristics. Therefore, the porcine pepsin submitted to HPH process can be a suitable alternative for the production of cheese.
منابع مشابه
Microsciadin, a New Milk-Clotting Cysteine Protease from an Endemic Species, Euphorbia microsciadia
In the present work, a new branch of biotechnological advantage of the latex of an endemic perennial plant, Euphorbia microsciadia has been introduced. A novel cysteine protease, designated as microsciadin, was purified from the latex of Euphorbia microsciadia by a combination of sequential usage of SP-Sepharose Fast Flow column in two different pHs and a final gel filtration ...
متن کاملImmobilization of Subtilisin Carlsberg on Modified Silica Gel by Cross-linking and Covalent Binding Methods
Proteases are important enzymes that their role in various industries is undeniable. However, keeping enzymes stable during its activity in harsh conditions is so important. In this study, protease enzyme was immobilized on the porous silica particles and its stability in different temperatures and pHs was evaluated. First silica particles were aminated by 3-aminopropyltriethoxysilane then the ...
متن کاملEffect of High Pressure on the Porcine Placenral Hydrolyzing Activity of Pepsin, Trypsin and Chymotrypsin
This study investigated the effects of protease treatments (trypsin, chymotrypsin, and pepsin) under various pressure levels (0.1-300 MPa) for the characteristics of porcine placenta hydrolysates. According to gel electrophoretic patterns, the trypsin showed the best placental hydrolyzing activity followed by chymotrypsin, regardless of the pressure levels. In particular, the peptide bands of t...
متن کاملEffects of Ultrasonic and High-Pressure Homogenization Pretreatment on the Enzymatic Hydrolysis and Antioxidant Activity of Yeast Protein Hydrolysate
Protein hydrolysate is highly regarded as a source of naturally occurring antioxidant peptides. The purpose of this study was to investigate the effect of Ultrasonic (Frequency, 20 KHz; Amplitude, 50%; Time, 30 min) and high-pressure homogenization (Power, 1500 bar; Rated flow, 10 dm/h) pretreatmenton the enzymatic hydrolysis and antioxidant properties of yeast protein hydrolysate obtained from...
متن کاملStudy on Activity and Stability of Proteases from Bacillus Sp. Produced by Submerged Fermentation
Objective: Investigations were carried out to isolate bacteria from saline-alkali soils and determined optimized alkaline protease activity and stability produced by a wild strain of bacillus sp. in submerged fermentation (SMF). Methods: Optimum temperature for enzyme activity in the crude extract was 40 ◦C at a pH between 8.0 and 9.0. The studies on pH stability showed that the enzyme...
متن کامل